nrf5340 - CONFIG_BOOTLOADER_MCUBOOT=y in prj.conf prevents net core working

Question

Hi,
I am currently using NCS 2.2.0, Zephyr 3.2.99, with a nRF5340 custom board.
The application core started with BLE Peripheral sample and I have since added my own integrations.
The net core is populated with the Zephyr HCI RPMsg sample as child image.
The main prj.conf includes

CONFIG_BOOTLOADER_MCUBOOT=y

This adds the following configuration for the child application

CONFIG_FPROTECT=n
CONFIG_MCUBOOT_SERIAL=n
CONFIG_BOOT_SERIAL_UART=n
CONFIG_LOG_BACKEND_UART=n
CONFIG_USE_SEGGER_RTT=y
CONFIG_RTT_CONSOLE=y
CONFIG_CONSOLE_HANDLER=n

and it breaks the net core functionality.
Actually bt_enable() fails with error messages

[00:00:01.447,570] <err> bt_hci_driver: Endpoint binding failed with -11
[00:00:01.454,895] <err> bt_hci_core: HCI driver open failed (-11)
[00:00:01.461,761] <err> ble: BLE init failed [-11]

Everithing works fine if I rebuild with

CONFIG_BOOTLOADER_MCUBOOT=n

Regards

Gabriele · Accepted Answer

I've solved. The correct choice for the net core image is /build/hci_rpmsg/zephyr/merged_CPUNET.hex, not /build/hci_rpmsg/zephyr/zephyr.hex.